An unwritten constitution
The lack of a single and fixed written constitution gives certain clear advantages to the people of the United Kingdom (here called the ‘English’ for short; though the law considered below is English and Welsh, and mostly affects the Scots). We do not have to ask permission to do anything, unless a law requires that we do (eg to walk on someone’s land, which is prevented by common law trespass). We are therefore free to do what we want, unless the law – common law, statute or delegated legislation – says we cannot.
For example, the common law says we may not kill (derived from the ten commandments); statute law says we may not drive more than 30 per hour in certain (mostly built up areas); and there are a variety of mostly statutory offences in between. The common law asserts that we have a duty of care towards others reasonably proximate to us (and enables us to sue in tort if someone breaches their duty of care: eg by negligently injuring us in a car accident). It is part of the system of having a fair trial, protected by the common law, that an individual should be entitled to take legal advice without anyone – but anyone – knowing what was that person’s legal advice (known as ‘advice privilege’).
The rights or freedoms, and restrictions, set out above long pre-dated Human Rights Act 1998 and will survive it. Unless they specifically curtail every right and freedom they can think of, no Government can remove most of what HRA 1998 protects. I personally think what the Tories propose is historically illiterate, legislatively coarse politics in a very subtle area of law over which politicians since 1688 have wisely trodden only very warily; and they should continue so to do.
Effects of Human Rights Act 1998 on English law
What the Human Rights Act 1998 has done is to assert: first that the Convention for the Protection of Human Rights and Fundamental Freedoms 1950 formally applies in England. This only confirms for us many of the rights which we have for long assumed. This is unsurprising: the Convention was written mostly by English common lawyers. And we will continue to assume the same rights whether or not HRA 1998 is repealed. As Lord Cooke put it, in a case in the House of Lords: ‘conventions, constitutions, bills of rights and the like respond by recognising, rather than creating, [rights]’. Lord Cooke is saying, things like HRA 1998 is nothing new: the rights were there long before the Act. The rights continue unless parliament specifically excludes them or restricts them (like telling us we cannot drive too fast; or may not assault or bodily harm another person).
Secondly the Act requires English judges to ‘take into account’ existing Convention jurisprudence (HRA 1998 s 2(1)). That is to say, it does not make English judicial decisions subject to the decisions of the European Court (as some politicians seem to think).
Thirdly, laws must be interpreted so far as possible to make them compatible, or to comply, with Convention rights (s 3); and if the High Court thinks they are not it may so declare (s 4), which discourages Parliament from passing laws which are contrary to rights specifically protected by the Convention. This is the bit which the more primitive politicians find unsatisfactory. They find it hard to accept a higher authority based on a very few fundamental rights.
The Convention will remain, whatever happens to Human Rights Act 1998; just as will our common law. Most English judges will follow its principles since they are part of our common law anyway. For the vast majority of English people the repeal of the present Act would not alter their individual rights in any way (for example, the European Convention 1950 has nothing to do with state benefits; the right to health and a national health service or education: those are guaranteed by altogether separate legislation). Only a tiny minority of English people are homosexual serving soldiers or prisoners who want to vote in elections (whose rights, as it happens, are protected by Convention jurisprudence).
The Act has two particularly civilising features as I see it: it provides a mechanism for checking judicial decisions against certain norms of rights and freedoms (eg should the mother of a child, entitled to stay here, be deported where it affects the child’s welfare: H(H) v Deputy Prosecutor of the Italian Republic, Genoa (Official Solicitor intervening)  UKSC 25); and it puts a check on the more extreme actions of individual state legislatures (which is what the Tories resent).
In a further note I will take some topical examples of the Convention in operation – or as it might be in operation; and of its relationship to the common law (already considered to a degree in https://dbfamilylaw.wordpress.com/2014/09/27/rights-freedoms-and-the-common-law/ ).
(1) What should be the rights of a man who has been convicted of abuse on one or more children on his seeking parole at the end of the minimum period which he should serve for a life sentence?
(2) What rights to privacy should a person have against the press making false or exaggerated reports against them (eg the parents of Madeleine McCann); or of making any reports if it interferes with their family life?
(3) What protection should a person have where s/he has informed a child protection department of abuse by A, where A is involved in separate court proceedings in relation to another child (and may be a danger to that child).